摘要
积雪深度D是水文模型和气象预测中的重要参数之一.基于新疆乌鲁木齐站1961-2013年积雪深度D及气象资料,分析了积雪起止日期、持续期特征和D的时间变化规律,并对比了不同模型对于D过程变化的适配效果.此外,对最大积雪深度Dmax进行了趋势检验,并简要分析了气象要素对D和Dmax的影响.结果表明：乌鲁木齐积雪的持续期在73-207 d范围变化,平均持续141 d,积雪开始日期和终止日均呈推迟趋势,积雪持续期呈增加趋势,但其趋势均不显著.可将积雪年内的D变化类型分为多峰缓变型、右偏型、尖峰型以及平峰型4种,分别用不同模型适配后发现整体上模拟效果较好的是Gaussian函数.在1961-2013年53 a期间的Dmax不具有自相似结构,但有显著上升趋势.气温尤其是最低气温与的D相关性最好,冷季降水总量与Dmax有的正相关关系,表明气温和同时期降水与积雪变化关系密切.春季迅速升温过程及一定的累积积雪深度可能令融雪型洪水爆发,其对应的年型为尖峰型和平峰型.
Snow cover depth（ D） is one of the important parameters for hydrological model and meteorological forecast. Based on snowcover depth and meteorological data during 1961- 2013 at rümqi Station,the initial date,the ending date and the duration of snowcover and the temporal variation of D within a snowcover year were analyzed. The fitting effects of quadratic function,Gaussian model,Lorentzian model and lognormal model for D process were compared. In addition,the trend test of the maximal snowdepth（ Dmax） was conducted; the influence of climate factors on D and Dmaxwere also discussed briefly. The results showed that the duration of snowcover in rümqi lasts for 73 to 207 days,with an average of 141 days. Both the initial date and ending date are postponing and the duration of snowcover is increasing,but not significantly. The time-curves of D within a snowcover year can be classified as four types,i. e.,multi-hump and flat type（ a）,right-skewed type（ b）,pinnacle type（ c） and flat hump type（ d）. After the D series within a snowcover year being fitted for four curve types,it was found that the Gaussian function was generally good. Thus,the annual variations of the three parameters in Gaussian function over 1961- 2013 were obtained. There is no auto-correlation structure in Dmaxseries,but there is a significant upward trend in it. Among the climate factors,air temperature,especially the minimal temperature,has negative correlation to D; while precipitation within cold season has positive correlation to Dmax. Fast increasing of air temperature in spring and enough snowcover depth may result in snow-melt type flood,which usually corresponds to the time-curves of D of pinnacle type and flat hump type.
出处
《冰川冻土》
CSCD
北大核心
2015年第3期587-594,共8页
Journal of Glaciology and Geocryology
基金
国家自然科学基金新疆联合基金项目(U1203182)
公益性行业(气象)科研专项(GYHY201106007)
西北农林科技大学基本科研业务费(YQ2013006)
国家自然科学基金项目(41271083
41201062)资助
